Sigma 135 400mm f/4.5-5.6 DG RF APO Aspherical Ultra Telephoto Zoom Lens for Nikon SLR Cameras Lens Construction - 13 Elements in 11 Groups Angle of View - 18.2 - 6.2 degrees 9 Diaphragm Blades Minimum Aperture - F32 Minimum Focusing Distance - 200-220cm, 78.7-86.6 inches